1. Field of the Invention and Contract Statement
The invention relates to shipping containers for radioactive or other hazardous materials, and more particularly to closures and seals for such shipping containers.
2. Discussion of Background and Prior Art
Some of the shipping containers for radioactive and hazardous materials use closures which embody flanged joints. Such closures are somewhat bulky and do not provide the degree of strength desired due to the nature of the materials to be shipped.
Attention is drawn to U.S. Pat. Nos. 4,195,457, 3,693,822, 3,613,939, 3,484,317 and 2,889,069.